Preheat oven to 350 degrees. Spray a 9 x 13 baking dish with non-stick cooking spray and set aside.
Peel potatoes and place into bowl of water. Using a mandolin slice potatoes to a 1/4 inch thickness. Drain & place slices into a microwave safe bowl. Place wet paper towels across the potato slices. Microwave for 1 1/2 minutes. Stir. Cook another 1 1/2 minutes and stir. (May take 3-4 times until a fork can go through easily & potatoes are par-cooked.) Set aside.
Meanwhile brown up ground beef and soften onion in same large skillet over medium high heat. Drain excess grease out of skillet. Season with salt, black pepper, garlic powder, onion powder, smoked paprika, and oregano. Stir to combine.
Add to seasoned ground beef, cream of soups, beef broth, and milk. Stir to combine. Turn off burner.
Place 1/2 of the tender sliced potatoes into bottom of prepared baking dish. Top with 1/2 of the meat mixture evenly. Top with 1/2 of the shredded cheese over meat mixture. Top with remaining potatoes evenly. Top with remaining meat mixture. Top with remaining cheese.
Cover with foil tightly. (TIP: Spray bottom side of foil with non-stick cooking spray to keep cheese from sticking to foil.) Place baking dish onto a baking sheet. Place into preheated oven for 45 minutes. Remove foil and bake an additional 30 minutes or until potatoes are tender and cheese is golden brown. Let sit on counter for 10 minutes before serving.